1. Field of the Invention
The present invention relates to orthopedic surgical reamers and more specifically to drivers for such tools.
In the field of orthopaedic surgery, it is often necessary to remove bone material to enable implantation of prosthesis to repair joints in the human body. Patella cutters and acetabular reamer cups and glenoid reamers are surgical tools which are used in surgery for the insertion of artificial joints. Acetabular reamer cups are used to cut hemispherical cavities in pelvis bones for the insertion of artificial hip joints. Patella cutters are used to shape the underside of the patella or knee cap during knee replacement surgery. Glenoid reamers are used to cut hemispherical cavities in shoulder bones for the insertion of artificial shoulder joints. Patella cutters have a complex arrangement of precisely shaped cutting edges arranged around an axis of rotation for cutting the patella. Acetabular reamer cups and glenoid reamers have a complex arrangement of cutting edges arranged on a spherical surface around the axis of rotation of the cup.
A number of tools have been developed for this purpose and include reamers having generally semi-hemispherical configuration with cutting elements on them so that a corresponding semi-hemispherical hollow can be formed in the bone material for providing a foundation for the repair of the joint.
There are two major driver styles in the field, one of which is for the Othy style manufactured by Symmetry Medical, Inc. and the other style manufactured by Precimed SA of L'Echelette, Switzerland. Although these both have semi-hemispherical cutting heads, they have different interfaces between driving tools with which they are associated. The Othy style has a crossbridge element. This element is a bar extending between the circumference of the hemisphere and having a circular expanded section in the middle. Numerous arrangements are available for securing this device as exemplified by U.S. Pat. No. 6,854,742. Alternatively, the Precimed reamer has a crossbar shape in which two circular cross section bars intersect at the center and extend to the walls of the hemisphere. An example of a driver for this type is found in U.S. Pat. No. 5,658,290 in which a bayonet interconnection is provided between the reamer and the driver.
Typically, surgeons use specialized drivers for each of the reamers. The drivers connect to a source of power and have appropriate handles for guiding the operation of the reamer by a surgeon. If a surgeon has one of the adaptors, it is difficult to utilize the other type of reamer since it requires a specialized driver for that reamer. It has been proposed in U.S. Pat. No. 7,115,119 to provide a dual adapter that accommodates both the Othy and the Precimed reamers. However, this style of dual reamer requires investment in a new reamer driver assembly to connect with the two different styles. In addition, this type of driver has a bayonet interconnection in which the assemblies are inserted axially and then a rotational movement, in accordance with a bayonet connection, is provided to lock the elements in place. This type of action slows the process of utilizing a new reamer because of the additional movement, But, more than that, the release of the device, after it has been in the surgical environment, is more difficult because it requires holding the reamer to reverse the rotational movement and then axial movement to finally free the reamer.
What is needed in the art, therefore, is an adapter for surgical reamers that enables rapid and immediate connection and disconnection of the reamers.